The annual lighting of the eight-branch Hanukiah is about to commence in Jewish homes around the world. Each night an additional flame is lit, as the mythic celebration of the triumph of light over the forces of darkness is again enacted. The symbolism is universal. Every culture has its cyclical rituals of renewal and regeneration, often embracing the motifs of fire and light. Christmas is upon us, and Diwali has passed. And this year the first night of the festival of Hanukah - tomorrow - coincides with the winter solstice. Even our secular calendars mark the event: the hours of daylight will slowly increase, and with the increase of light, the earth renews itself, offering us the hope of the springtime to come.

This need for a renewal of hopefulness is especially true at a time of financial instability, ecological collapse and escalating concern about the precariousness of our existence on a planet whose resources we are rapidly exhausting. When Barack Obama, following his election as US president, spoke of "those who have wondered if America's beacon still burns as bright", he was drawing on imagery derived from biblical prophecy about the hoped-for survival of the community of Israel (Isaiah 30:17).

And the sense of renewed hopefulness around the world that has accompanied Obama's election emerges from his articulation of where he believes the "true strength" of America comes from: "not from the might of our arms or the scale of our wealth, but from the enduring power of our ideals". This is a secularised version of the biblical vision put into the mouth of the prophet Zechariah (4:7), who declares in the name of God that the nation will succeed "not by might, nor by power, but by My spirit".

It is this sentiment that underlies - and is quoted on - the festival of Hanukah: that although the eight-day holiday originates in a historic memory of a military victory in a guerrilla campaign two millennia ago against foreign (Graeco-Syrian) occupiers, a nation's true success is to be measured in non-material ways; that there are other values - values of the spirit, the soul, the heart - that count for more than money, arms, possessions, material wellbeing.

Yet this lesson took centuries to emerge. Against all odds, a group of Jewish religious nationalists had taken back the temple in Jerusalem and re-dedicated it to their God - Hanukah means "Dedication" - but what started as a sort of old soldiers' holiday transmuted into an annual opportunity to reflect on the ways in which each generation has to battle against oppressive cultural and material forces to retain its grasp on certain transcendent spiritual values and ideals.

Thus a legend arose, in relation to Hanukah, that when the temple's cultic candelabrum (the menorah) came to be re-dedicated, there was but a single flask of undefiled oil to be found, enough for one day only. And yet - a miracle! - it lasted for eight days, till fresh supplies arrived. The Talmudic rabbis used this mythic narrative to justify the continued celebration of the "festival of lights", suppressing its militaristic origins in favour of its symbolic resonances: the faith required to persevere against the odds; the belief that sparks of enlightenment can outshine and outwit the darkness grafted to our souls; the audacity to hope that integrity and truthfulness can illuminate - and thus win out over - falsehood and destructiveness.

This vision became the spiritual core of Hanukah. The hope for the victory of "light" over "darkness" has a universal resonance. In his acceptance speech in November, Obama highlighted the "challenges that tomorrow will bring" - including "a planet in peril". This Hanukah I wonder what new "miracle" we now need? Is it the realisation that one may suffice when we imagine we need eight? That less is going to have to mean more? That our material resources are finite - including our oil - but our inner resources are beyond measure? That faith means depending on each other more than ever before?